Helicity Structure of Nucleon Resonance Electroproduction and the Symmetric Quark Model*
نویسنده
چکیده
The symmetric quark model with harmonic forces is shown to lead to a rapid change with q2 of the helicity structure for elec troproduction of the second (D13) and third (F15) nucleon resonances. Preliminary results of coincidence measurements of pi-zero electroproduction in the resonance region are found to disagree with this prediction. Some further experimental tests and theoretical consequences of this failure are discussed. (Submitted for publication) * Work supported in part by the U. S. Atomic Energy Commission. j+ NATO Fellow, 1970-1972.
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